A new toxicology study states that rats eating genetically modified food and the weedkiller Roundup develop huge tumors and die. But many scientists beg to differ, and a close look at the study shows why.

Genetically modified organisms (GMOs) have always been a controversial topic. On the one hand are the many benefits: the higher crop yields from pesticide- and insect-resistant crops, and the nutritional modifications that can make such a difference in malnourished populations. On the other side is the question that concerns many people: We are modifying the genes of our food, and what does that mean for our health? These are important question, but the new study claiming to answer them misses the mark. It has many horrifying pictures of rats with tumors, but without knowledge about the control rats, what do those tumors mean? Possibly, nothing at all.

The recent study, from the Journal of Food and Chemical Toxicology has fueled the worst fears of the GMO debate. The study, by Italian and French groups, evaluated groups of rats fed different concentrations of maize (corn) tolerant to Roundup or Roundup alone, over a two year period, the longest type of toxicology study. (For an example of one performed in the U.S., see here.) The group looked at the mortality rates in the aging rats, as well as the causes of death, and took multiple samples to assess kidney, liver, and hormonal function.

The presented results look like a toxicologist’s nightmare. The authors reported high rates of tumor development in the rats fed Roundup and the Roundup-tolerant maize. There are figures of rats with visible tumors, and graphs showing death rates that appear to begin early in the rats’ lifespan. The media of course picked upon it, and one site in particular has spawned some reports that sound like mass hysteria. It was the first study showing that genetically modified foods could produce tumors at all, let alone the incredibly drastic ones shown in the paper.

But can GMOs really produce such huge tumors? This paper isn’t convincing. Following the release of the study, numerous scientists questioned the findings, citing “anomalies throughout the paper that normally should have been corrected or resolved through the peer-review process.” In particular, there are problems with the statistics performed on the data, the way the data were presented, and the numbers and types of animals used in the study.

First, the numbers. The authors examined groups of male and female rats in four different conditions: GMO food alone, GMO + Roundup, Roundup alone, and controls (normal food with no Roundup). For each experimental condition, there were three different doses of either the GMO maize (as a percent of the diet), Roundup, or both; the amount of doses of Roundup were all well below the approved doses. The 20 groups each contained 10 individuals, for a full total of 200 rats (100 male and 100 female). While 10 rats per condition might seem low, in a power analysis used to detect differences in response to, say a Roundup and non-Roundup condition, this would probably be OK. But how many final comparisons were the authors making? In the end, the authors compared each experimental condition to the same group of control rats, something that could severely bias the results. In most well-performed experiments, there would be a separate group of control rats for each condition, the GMO food alone, the GMO + Roundup, and the Roundup alone. The controls used for the study, as Anthony Trewavas, a cell biologist at the University of Edinburgh, pointed out in a press release response, are “inadequate to make any deduction.”

Then of course, there is the question of the animals themselves. Who were these rats? As it turns out, the rats used in the study were the Sprague Dawley rat strain, a widely used strain in biomedical and behavioral research. Unfortunately, this strain is prone to specific diseases…including the development of tumors. Up to 57% of female Sprague Dawley rats have been shown in other studies to develop tumors, especially mammary tumors, spontaneously. Males develop tumors at fairly high incidence as well. But in their striking mortality numbers for the study, showing the type and incidence of tumor development, the authors of the study do not show any of the control groups, and so we cannot actually compare the death rates of any of the GMO and Roundup exposures to controls. Tom Sanders, head of the Nutritional Sciences Research Division at King’s College London, pointed this fact out in the press-release response. “Most toxicology studies are terminated at normal lifespan i.e. 2 years. Immortality is not an alternative.” A careful read of the findings shows that the control group suffered a “spontaneous death rate” of 30% for males and 20% for females. But the authors do not state what caused the death. Did the dead animals develop tumors? Did control animals that survived develop tumors? We don’t know. The authors did not show us.

Not only do they not show us, they do not present statistics to tell us the full story. In comparison to the 50% male death rate for the GMO maize diet…is a 30% death rate in controls any better? There are no statistical analyses of how death rates compare between the different treatment groups and controls, only percentages. The way the data were analyzed is also unusual and highly complicated. This struck many of the scientists who read the study (including me) as odd. When comparing groups of doses as these authors did, there are simple enough statistical tests that will easily differentiate among the groups. Why were these tests not used? Why were the authors required to develop a highly convoluted analysis for something as simple as mortality rate?

In the end, while the results of the study look very drastic, there are too many issues to conclude that GMO maize and Roundup cause tumor formation. All we can really conclude is that rats who are prone to develop tumors…develop tumors, whether they are fed GMO maize, Roundup, both, or neither. In addition to the problems with the paper itself, the results contradicts a large amount of literature showing now difference in health consequences following consumption of GMOs. The potential health consequences of roundup exposure and GMOs should be carefully studied and evaluated, but studies like this one do not provide the answers, and only add to the hype.

And as some critics have pointed out, if GMO maize and Roundup, both highly utilized agricultural products, really caused a drastic increase in tumors, why haven’t we seen this in humans? Mark Tester, research professor at the Australian Centre for Plant Functional Genomics at the University of Adelaide, expressed this concern to the Science Media Centre: “The first thing that leaps to my mind is why has nothing emerged from epidemiological studies in the countries where so much GM has been in the food chain for so long? If the effects are as big as purported, and if the work really is relevant to humans, why aren’t the North Americans dropping like flies?!” A very good question.

Addendum, September 27, 2012: As commentor Nico points out, the authors did indeed include control data lines in Figure 1, so the controls were presented. However, this does not change the problems with the paper, and the fact that we were never presented with hard numbers and standard errors for the controls or any of the experimental groups. Further, the authors of the paper noted that a percentage of their control rats died during the experiment and were taken out of the study. I have to say I find that rather odd, especially considering this is a study on mortality. The other issues with the paper still stand.

Great! What the public needs is sound, scientific facts, no fear mongering. Thank you.

https://sites.google.com/site/njpillon/ Nico

Very interesting commentary, and after having read the study, I can agree with your concerns about statistics. However, the control groups are presented in the figures, and even without statistics, there is a trend that controls develop less tumors. As any scientific study, is has weaknesses (time points, model…).

However, I completely disagree with your last paragraph about humans. A human lifespan is about 80 years, and the first GMO in our diet arrived in the 90’s. We have only 20 years of exposure, with increasing levels overtime as more and more GMO were authorized. Human rarely develop tumors before their 40’s and as a scientist, you know how difficult this can of epidemiological studies can be…

I guess my main point is that your same arguments against this study can be applied to the studies showing no effects. From my perspective, I like this study just because it goes against the common pseudo-admitted fact that GMO are not toxic. Which is really not scientifically proved.

I have seen so many studies supporting safety that are also statistically flawed.

The fact that labeling on GM foods is not required means that consumers are being experimented on unethically. Most every ethical review community requires informed consent. Consumers are guinea pigs without consent.

Monsonto’s got their man heading the FDA. They want to use 2,4-d (a 50% component of agent orange) on crops now because over use of roundup resulted in super weeds.

Citing GMO epidemiological studies proves we are guinea pigs without consent, and these studies aren’t sufficiently controlled either because GMO have been released in the environment.

http://peicurmudgeon.wordpress.com/ peicurmudgeon

Your last statement is one that i often ask the people who are against many of the aspects of modern life that are supposed to cause cancer. Shouldn’t the science be working the other way? First we find an increase in cancer or some other disease and try and find a couse? Many of these studies seem to search for a cause without a problem.

http://appliedmythology.blogspot.com Steve Savage

Nice critique. this is a perfect example of “agenda science” and what one wonders is how this ever got through peer review. This journal should be embarrassed

Politicarl

I haven’t seen the study being evaluated here so I can’t really make comments specific to it. It does seem, though, that there are some serious shortcomings in it, or at least in reporting its results.

But that does not in any way let GMOs off the hook of doubt. We are playing with our FOOD supply here – FOOD that is essential to our survival. We are also affecting the non-modified organisms that interact with the GMO crops. The pollinators are affected, quite possibly to their detriment as well as to ours. GMO pollen escapes into the wild and influences non-GMO crops and wild plants. Pests – plants, animals, micro-organisms – are affected in unknown and unpredictable ways.

There is enough research already strongly suggesting, if not clearly demonstrating, that there are serious questions about the effects and potential ramifications of GMOs. As inadequate and imperfect as currently available research might be, what we already know indicates our need to learn a whole lot more.

GMO technology is far outpacing our knowledge and understanding of the ramifications of using and spreading it. Much about GMOs is hidden from view to protect investments and patents, making it next to impossible to do adequate independent research, thus forcing us to rely on the information provided by the very industry seeking to develop, promote and profit from this technology. Corporate success is not predicated on wisdom about what is safe and wise to do, it is predicated on the bottom line of corporate spreadsheets.

We need to proceed with much greater caution. We need greater access to all the information about GMOs. We need high quality INDEPENDENT research. We need to slow down use of GMOs to give us time to determine the best course to follow. And, for the GMOs that are already in use, we need clear and honest labeling so we can decide for ourselves whether or not to use GMO products that might be dangerous to consume.

If the GMO industry is afraid of unfair discrimination based on the “scary” GMO label, then the industry needs to do all it can to facilitate independent research to demonstrate as clearly as possible that GMOs are safe and desirable, OR to allow demonstration that GMOs are unsafe and undesirable and take the consequences. To not do that is to arrogantly put money above the health and well-being of humans and of our environment.

Panicky reactions are entirely justified considering the potentials for serious negative ramifications due to GMOs, in light (or darkness) of the obvious lack of corporate concern for our welfare. Current knowledge and understanding of GMOs in no way substantiates their safety. All corporate resistance to adequate independent study and to labeling of currently available GMO products only feeds our concerns, fears and panic. What are they hiding?

julianpenrod

The issue of genetically modified foods is shaping up to structurally be equivalent to the matter of climate change, only, here, the “science” community is taking up the tactics of the anti global warming muckrakers.

First, note the attempt to boil the problem down to misrepresentative pithy dismissive phrases like “More Sensational Than Sense”. “Hysteria” is decried by the “science” community when used by climate change denies with respect to reports of global warming, yet here is Scicurious using the very same word to try to derisively bring to a hallt all consideration of the genetically modified question! Then Scicurious attacks one claim for not being legitimately presented, while at the same time failing to validly present your side. The, frankly, suspiciously anonymous “Scicurious” complains about no information about control groups for the study, yet only claims that “numerous scientists” questioned the report, without mentioning how many, or how few, “scientists” those were!

And, quite frankly, it is patently illegitimate to require a separate control group for each tested diet scenario! Is the anonymous Scicurious saying that rats fed normal food in the sequence of experiments that fed other rats RoundUp would have different rates of disease than those who were fed normal food, but were listed in the collection of experiments where rats were fed only genetically modified corn but no RoundUp? Common sense is supposed to be represented in “science”, not finding excuses for artificially jacking up the cost of “experiments”! In fact, the behavior of control groups is not represented as having changed for a century or more. They could take the results of a control group of rats from before 1900 and use that as a comparison for all “experiments”! But that wouldn’t allow for increasing grant requests!

And note condemning the use of Sprague Dawley rats as being “prone to specific diseases”, suggesting they are not valid tests. Then why are they a strain, as Scicurious admits, is “widely used”? How widely? How many fraudulent “studies” attacking tobacco used the rats that Scicurious condemns as useless for such a study? Why breed a strain that is so susceptible is, as Scicurious tries to suggest, they mean nothing in study to determine food safety? Scicurious suggests, and that may be all, that Sprague Dawley rats have a 30% tumor death rate in the control gorup, so why would such a strain be bred and “widely used”?

And note the assertion that genetically modified foods and products like RoundUp have been used for a “long” time, but there are no increases in cancer rates. Is Scicurious really going to say that “medical” records don’t listw a major presence for cancer in the U.S. and many other nations? Is Scicurious going to deny that, as one form of cancer subsides in numbers in the U.S., others automatically move in, to keep the rate constant?

And, while Scicurious may not have broached the subject, a number who commented on the subject elsewhere on the net suggested ulterior motives for those fighting genetically modified foods, just like the climate change denies say those proclaiming global warming are only doing it for personal profit.

This is wholly equivalent to the climate change situation.

Gabriel

“Why aren’t North Americans dropping like flies?”

So the implication is the American people are being experimented on BEFORE the rats. I like how the author endorses this particularly bad question.

We’re being tested on. This doesn’t make you mad? This is the first study to examine the entire lifetime of gmo consumption. These products should be extensively studied, not just over a lifespan but over generations. And that, before we eat them.

Why do you fill your lungs with air to shout this study down? Why aren’t you comparing it to all the other 2 year rat studies? Oh, because there aren’t any to compare it to. That little factoid gets short shrift in this embarrassing apology for the US gmo policy. I hope the author of this article stays in a job and keeps their family fed. It’s just too bad she’s going to have to go on living scared and utterly compromised in order to do it.

Mr. Anthony

When in doubt: run in circles, scream and shout.

http://scientopia.org/blogs/scicurious/ Scicurious

Nico: The control groups are presented in terms of total numbers of tumors in Table 2, but the presentation is very strange, and does not actually end up including the total number of control animals. In figure 1, there are no mortality line curves for the controls presented, and the bar graphs show now significant differences between controls and dosages in types of tumors seen. Yet they say that the treatments cause huge tumors.

The last paragraph about humans is a quote from another scientist, but I do agree with it. IF this study is correct, humans should be showing a massive increase in tumors, as the authors of this study saw huge presentations of tumors at early points in the lifespan after roundup treatment, and at doses far, far below those approved for use in the US. There is no evidence of an increase in cancer incidence as linked to consumption of GMO maize or in response to roundup exposure.

Sarah

200 rats seems like a good number but with four different treatment groups and the expectation that there will be sex specific effect you would really have to expect a pretty dramatic effect from GM corn to get any kind of significant effect. Like, you know, arsenic poisoning or something.

I think even the most ardent GM opponent would probably expect something more subtle. Finding an effect with this few rats is like expecting GM food to kill off half your neighborhood. That alone make the study seem quite fishy.

But on the other side I’d say that it’s scary this is in our food an this is the ONLY rat study done on long term exposure to these pesticides. The regulatory studies, it says, only require 10 rats in a 3 month trial. If that’s an accurate portrayal of the state then that’s a joke.

The authors of the paper are more temperate than the authors of the press release (as is often the case).

christine

I don’t want to run in circles, scream or shout….I just want to know if something genetically modified so that I can make an informed choice. We already hold the solution to world hunger if we were willing to feed humans before livestock. The earth provides plentifully, but humans insist on messing it up and making things complicated. If we were living in balance, we wouldn’t need to perform byzantine experiments on the food supply. And don’t forget that Monsanto and others want to patent all their seeds and force farmers to buy new seed every year. It’s really all so unnecessary.

Anonymous

An author with a PHD not using a real name = probably hired by Monsanto!

Michael

Thanks to all for your comments. We need to keep the conversation going. I would like to add my piece.

As someone who has two science degrees I am of the opinion that scientists on the whole are very focussed on the finer details at the expense of the bigger picture. I appreciate the need for good science – without it there is little progress. However, lets consider what is involved in the bigger picture

1, Our food chain
2, Sudden introduction of genetically modified organisms that would that would naturally take….millions? of years to evolve
3, Profit motivation on the behalf of any manufacturer
4, The irreversibility of introducing genetically altered plants into the environment

Lets put the finer detailed debate about stats aside for one minute and consider the wider picture…

Animal studies are only ever indicators for possible risk to humans
If an animal study indicates an increase in bad health outcomes on exposure to the food, surely it is wise not to be dismissive and proceed to the next level.

Some who debate the stats seem also to confidently dismiss any possibility that the study has picked up a real effect. Given what is at stake, such a position is based more on faith than good science and is niave in the extreme.

Georg

What about that
“peer” rewieved “Journal of Food and Chemical Toxicology”?
Why did they publish such obvious nonsense with political bias?
Georg

Glen

The quote from Mark Tester is of so little comfort when we know so many cancers are on the rise particularly in the US with similar trends emerging more recently in Europe.

The first thing that leaps to my mind when reading that quote is “What does Mark Tester have to gain with such a quote”. I can only guess, but this quote from his website under professional interests “…successful interactions with multinational companies such as Monsanto, Syngenta, Bayer and Pioneer-DuPont” raises some red flags with me.

Then there is the other big unanswered question: Where are the other long term studies that refute any of the assertions of the study at hand?

Mark

As a former editor of several scientific journals, I place the blame for this problem first on the editor’s shoulders that handled this paper, then on whomever was involved with the peer review and lastly on the scientific community as a whole. There are far too many editors who will blindly read the reviews and take them at face value. If only two reviews were sought and they conflicted, how do we know which one was given more weight? Everyone is very busy and the pressure to publish so that your productivity is viewed as high is greater than ever. Reviewers often provide hastily written poor reviews that reflect their inability to take adequate time to really scrutinize the science. Editors are in turn required to handle many more papers and thus, things like this slip through. All of this comes before we should worry about if these scientists for this particular study held any implicit or explicit biases that would further complicate their view of their work and how they performed it. If the science is poor, it should end there. Sadly, and more frequently an ever, this is not the case.

I’m much more worried about egregious patent protection given to Monsanto that seeks to prevent farmers from replanting their own seeds and leaves them open to liability if their fields become ‘contaminated’ with Roundup Ready crops. It’s almost like patents make no sense on self-reproducing ‘products’!

BigChan

“why haven’t we seen this in humans?”

Unethical.

Kyle

Bearing in mind that I am someone that doesn’t really have experience with experimental set up – can someone explain why you would need a different control group for each group being examined?

I would think that it would be best to keep the same group (in case there is any general bias within a certain group) – though I suppose that could be countered if you included an analysis of the different control groups. Is that what is supposed to be done?

Mr. Pierce

The need for sound science and reporting is real – we should call a spade a spade. I take issue, however, with the way Scicurious frames the issue. Yes, she writes in response to an article about the health risks associated with consuming genetically modified food, but, particularly in such a widely distributed publication, it is grossly irresponsible to paint the opposing arguments as one-dimensional, to cite only the health concerns related to eating GM foods. This is not only a human health issue. It is also about the link between genetic modification and the proliferate application of biocides and synthetic fertilizers responsible for alarming damage to the natural systems on which life depends. At best the author exhibits a lack of regard for the validity of the arguments against the use of genetically modified foods, and at worst she reveals what is either her own bias or surprising ignorance to the breadth of the issue.

The author cites the “many benefits” including higher crop yields and nutritional modifications but fails to mention the significant environmental health debt these modifications generate. Our current practice of growing modified foods works hand in hand with the practice of monocropping, the result of which is a food system that acts in fundamental opposition to ecological cycles and is causing increasing environmental devastation at an increasing rate.

For various reasons monocropping makes crops unusually vulnerable to pest infestation and disease. The widespread application of biocides (these are the poisons our food is being engineered to withstand) is a myopic attempt to account for the shortfalls the monocropping practice is inherently subject to.

We use synthetic fertilizers (that leach nitrogen, destroying watershed habitats) largely because monocropping renders soil unusable without artificial supplementation. But even after synthetic fertilizers are added, the soil is less able to hold water and leaches contaminants much faster than normal soil, which results in contaminated water supplies and aquatic habitat destruction.

I urge you to look at the bigger picture of what is happening to our food system and what it is doing to the natural systems on which we depend.

http://blogs.scientificamerican.com/scicurious-brain/ Scicurious

Mr. Pierce: I appreciate your concerns, I think that monocropping is definitely something to be considered in particular. I intended with this piece only to point out what parts of this particular study were exceedingly problematic, not to comment on the field in general.

22. Kyle: You would need a larger number of control animals in this study if you actually expected to show anything different from the treated population. They have so many treatment groups that basically anything statistical would come out in the wash, the more treatment groups you have, the more animals you need to prove difference from both baseline and from other treated groups.

8. julianpenrod: Scicurious suggests that the Sprague Dawley rat is a highly used group because they ARE. This does not make them less prone to tumors. Spragues are highly used in part because they are very calm and easy to handle. They are often used in things like studies on addictive properties of drugs, and can be a good model of diet induced obesity. And because they do get tumors at a higher rate, they can be used in cancer research. And while Scicurious does not deny that there are certainly high incidences of cancer in the US, they have not shown the drastic increase that would be implied by the findings of this study, which used doses much lower than those approved for agricultural use and saw incidences of tumorigenesis much higher than those seen in any human population. Scicurious does not deny that both sides of the debate have agendas, Scicurious only wishes to point out that this study, in particular, does not produce anything useful.

Scicurious: I’m sorry, but even in figure 1, the control group is presented (equivalent closest isogenic non-GM maize, dotted line). And except that we usually present mortality curve as a decreasing curve (survival), this way of presenting the data in perfectly suitable for time-course toxicological studies…

http://blogs.scientificamerican.com/scicurious-brain/ Scicurious

Nico: Ok, I looked at figure 1 again and I do see that you’re right, I thought that was a dosage group and I realize I was incorrect. I will ask the editors to correct my error with a noted edit. But I still have a major problem which this way of presenting the data, particularly the way of representing the SEM of the control group, which is not compared in any way with SEMs of any of the experimental groups. What does the SEM mean in comparison to the groups? Is it significant? I notice that the control line in the male/GMO section (top left) appears to show a higher rate of death, and there is similar at the bottom left in the roundup group. This is not mentioned. The females appear to show lower rates of death in control groups, but is it significant? These numbers are not given in the text. And many of the SEM areas are difficult to interpret. For example, in the bottom left of the figure, there are several grey areas mean to represent SEM. But what does the SEM mean? If the SEM corresponds with expected lifespans for the control group, it looks like nothing falls out of that window in any of the experimental groups, except possibly the females in the top panel. But the graphs are so difficult to interpret that it’s very hard to tell. This way of presenting the data is often suitable, but without full numbers in the text with SEMs (which are not given), it’s impossible to tell if there are significant differences.

To me we are not really free to choose one over the other. To prove the safety of a compound is tantamount to demonstrating the inexistence of something (an effect on the health, or the environment), which we know is impossible. We can only prove the toxicity. A very incomfortable asymmetry indeed! Facing which, we are almost bound to choose “a”.

“Which is wiser
a. To consider safe until proven toxic
b, To consider toxic until proven safe”
That is far too simplistic.

I agree that demonstrating safety is impossible, as every compound is toxic if you give a high enough dose. So the problem here is: from what concentration do we consider it toxic? That is why toxicological studies use the so called lethal dose 50: the dose that kills 50% of the animals. You can die from an overdose of water!

I would add, however, that suspecting toxicity is possible. For example if chemically similar compounds have shown toxicity. In that case, b is a wiser choice than a.

SilenceIsGolden

@#25 “Scicurious is pseudonymous, not anonymous”

I find this very questionable. I completely understand the need and wish to be anonymous on the web and even use a (or more than one) recognizable, trademark pseudonym of sorts when commenting. However, to completely and all the time publish, i.e. create content of some sort, under this pseudonym shows to me a clear wish to hide your identity in a way that is not justifiable under these circumstances. As a reader of a scientific opinion, I would like to be able to find out more about this person than just a bunch of other stuff written under this pseudonym and a vague reference on her/his/its website than this:

“Scicurious has a PhD in Physiology from a Southern institution. She has a Bachelor of Arts in Philosophy and a Bachelor of Science in Biology from another respected Southern institution. She is currently a post-doctoral researcher at a celebrated institution that is very fancy and somewhere else.”

What is she afraid of? Is she ashamed of her universities? Why? If she really thinks it doesn’t matter what university she chose, why use the qualifier “fancy?”

This is a strange behavior, and I find it even stranger that magazines like Scientific American and Discover support such anonymity.

Brent

What great comments. I can only add that I have lived through many “assurances” where industry-funded studies said there were no problems and any studies showing the contrary were ridiculed. One of those I remember the most was DDT. It was inexpensive, effective, and very popular. DDT was used for its broad-spectrum activity against insect pests of agriculture and human health. How many years did it take and at what environmental cost before “science” woke up, stopped supporting the manufacturer, and helped to ban it? Add to all of this the instances of Monsanto unethically putting small organic farmers out of business through patent infringement lawsuits because their GMO corn mixed with the small farmer’s corn. We need more organic, small farmers–that is where science should be focused and that is the most cost effective, not more totalitarian agriculture. Of course, Monsanto doesn’t own all the small farms, but it sounds like they’ve convinced you to promote their business and discredit studies to the contrary.

http://pleiotropy.fieldofscience.com Bjørn Østman

On top of all the problems with their analysis, something else is missing:=. If it was found that GMO maize cause tumors, we’d really need a causal explanation for that. Roundup is a poison, after all, and it is not difficult to imagine that it could interfere with some cellular function. But GMO maize is just maize where the genetic changes are decided on by humans vs. normal maize where lots of genetic changes are decided on by no one. It really makes no sense to make the blanket statement that there is something fundamentally different about genetic changes when they are done by humans.

This is an example of why I am dumping my subscription. Considering untested, except on the general public of course, experimentation in our medicine and food supply safe until proven otherwise is insane. This magazine is absolutely predictable in towing the corporate line in almost every instance regardless of countless non- industry supported studies that indicate danger to us lab rats. How many times in the last 6 decades have I watched this type of reporting go on without an apology even after the evidence of harm to humans finally becomes incontravertable. Our children are eating this experimental crap and the scientists you always place so much confidence in are just dabbling in our unimaginably complex world with profit minded blinders on.

Amos Zeeberg (Discover Web Editor)

@will: Do you think Discover is pro-corporate when it comes to climate change? We’ve been covering global warming unflinchingly since 1988.

Discover is pro-science, not pro-corporate.

https://sites.google.com/site/njpillon/ Nico

@Bjørn Østman: “It really makes no sense to make the blanket statement that there is something fundamentally different about genetic changes when they are done by humans.”

That is probably because you don’t know how the genetic modifications are done, and how random is the addition of a gene into DNA. Sometimes adding a new gene completely blunt another one, and depending on where in the genome it is included, the effect may be dramatically different. And these are parameters that scientists do not control.
They only select plants for the effect they want, which in this case is to resist to a pesticide. Doesn’t matter any other modification of the plant if this GMO has the effect wanted.

humphrey

Clearly this study needs to be repeated to provide relevant data with statistical significance values as obtained with animals subjected to less unnecessary pain.

It is pertinent here that the study is not the only long term study conducted – at least 4 long term or multi- generational studies found no carcinogenic effects with GM foods.

There does not appear to be any compelling reason to expect that harm to health would be any greater with GM food than with food from plants bred by “non-GM” techniques. Thus (1)to date (this study excepted) the many studies done show no harm from GM food (2) the genome is no more disturbed with GM techniques than with its non-gm counterparts – and is shown to be less so in some instances (3)metabolomic studies show that changes in the levels and existence of the thousands of plant metabolite are no greater and may be less with the GM technique.(4) harm to farm livestock given GM food now for many years and through many generations is yet to be reported.(5) The gene(s) inserted by GM techniques contain the same 4 chemicals as the existing genes in the plants (6) foods derived from non-GM techiques have been shown to affect health and are not safety checked – in effect we are guinea pigs for testing foods from non-GM breeding.

No food has ever been shown to be non-toxic – pre-GM some people died prematurely from cancers.It is impossible to prove absolute safety, an attribute that some still demand even though it is unachievable.

Clearly , there seems to be no reason to regard GM food as toxic but food from each new GM cultivar, as well as that from non-GM cultivars should be safety checked.

Plastic_Craft

How sad, you are just another scientific mercenary protecting big corporate interests for fear of losing your payroll / funding for self benefit.

Not that I think it really matters for the purpose of this conversation, but Discover IS corporate. So is by necessity pro-corporate. Discover can choose to try to cover things in a certain way, but in the end its purpose is to make money. Please note the corporate logo at the bottom left of the page. Kalmbach Publishing Co.

Blathering Blathiscope

I was under the impression that GM corn was not and is not fed to humans. That GM corn is used as animal feed or as ethanol source.

As Humphrey says, any food contains chemicals that can cause problems in high enough amounts. Some more then others. Yet I would much prefer to be aware of which foods I eat contain GM foods so I can vote with my money.

The evidence is clear from non GM life forms, alien organisms introduced into ecosystems often cause widespread problems and ecological changes that are simply impossible to control once started. From starlings to Scotch Broom Bush the Island I live on has seen many alien life forms that have wreaked havoc. Scotch Broom covers hillsides choking out all native vegetation. Starlings have forced out many native birds. Bullfrogs, once never seen before here are now prevalent in all our ponds and lakes. They are eating native reptiles, birds, mammals and insects.

They are competing for food and winning, destroying hundreds of thousands of years of genetic diversity in a few short decades.

The original live outdoor GM corn test was a perfect example of an abysmal failure. An example of humans ability to ignore warnings, under estimate problems, and most importantly, to show that there is so much we don’t know that a little bit of knowledge can be dangerous. The pollen spread many times farther then anticipated. The gene was found to have transferred to wild weeds and bacteria in the area. Known to be “impossible”.

Our knowledge of how transferred genes will behave generations from now, how viruses will be effected, and bacteria, is simply too little. But the corporations doing research in these areas are pushed to get their products to market as soon as possible for a myriad of reasons, but mostly so investors can get their investment back. That’s not a bad thing, but it can’t be the only, or major driving force.

In the context of GM food safety it is pertinent that a review of the relevant scientific studies conducted up to yr 2011 was published earlier this year – google “Assessment of the health impact of GM plant diets in long-term and multigenerational animal feeding trials: A literature review” In the review the authors conclude that “Results from all the 24 studies do not suggest any health hazards and, in general, there were no statistically significant differences within parameters observed ”.

In considering this review it important to keep in mind that 22 of the 24 studies were conducted , not by the multinationals , but by the public sector . Again, the authors indicate that they have no conflicts of interests and the review was funded , not by the corporate sector but by the French Nat. Center for Sci. Res. , the French Ministry of Agriculture and the University Paris-Sud.

The review should lay to rest the misconception that most of the safety studies conducted were done by multinationals and could therefore be treated with suspicion.

The review also refers to the many short term studies (eg 90 day rat tests) done and the finding that these showed no harm due to GM food.

Comment on the review by one scientist is given in ” Guest opinion: Two dozen studies show GM foods safe”

Jay Fox

Label the products, and let consumers decide if they want to be guinea pigs.

humphrey

Jay Fox , you have to realise that the labelling would demand much work by food producers and retailers . This would cause a significant increase in our food cost . Together with countless others , I do not want to pay more for my food – I have enough financial commitments now . We do not want to pay extra when there is information showing that GM breeding is no more likely to produce harm than non-GM breeding. The fairest approach would be to have food labelled as GM free if that were the case , combined with a GM label if the food had say more than 1% GM . Those wanting GM free food would then be responsible for the labelling costs .

No food can or has been shown to be absolutely safe and it has to be accepted that we are all guinea pigs for both GM and non- GM foods . We should be testing food products from all methods of plant breeding . I recall that a while back the new celery cultivar from non-gm breeding had to be discarded because of its increased promotion of an allergic response . Many non-GM foods would have to be taken off the supermarket shelves if we applied to them the same safety tests as we apply to GM foods.

Blathering Blathiscope

Suggesting that labeling would drive up costs is NONSENSE.

All it requires is for the source foodstuffs to be labeled. From there its easy. Either it contains GM, or it does not. It simply requires a single line item on the label.

Lets not be silly. The same was said about salt, fat, vitamins. All of which are labeled on processed food.

The title should be “Under-controlled”. Without a hyphen, “under” is a preposition, and since “controlled” is an adjective, it looks like there’s a noun missing from the title, as if maybe it was supposed to be “Under Controlled Conditions”.

Matt B.

We are modifying the genes of our food, and what does that mean for our health?”

I have to say I’m worried about the change in genes of foods that have been bred without genetic engineering. They’re bred to increase volume or calorie content, but possibly at the cost of nutrition.

“…the Sprague Dawley rat strain, a widely used strain in biomedical and behavioral research. Unfortunately, this strain is prone to specific diseases…including the development of tumors.”

That’s funny. In Douglas Adams’ The Meaning of Liff, “vobster” is defined as “A strain of perfectly healthy rodent that develops cancer the moment it enters a laboratory.” Once again, life imitates absurdist humor.

humphrey

Blathering Blathiscope , unfortunately (1) the matter of GM labelling is a lot more complex than just putting a label on for food components like salt or vitamins (2) there is the need to provide a bureaucracy to administer the labelling and (3) it is inevitable that there will be lawsuits on the matter . Accordingly the labelling must cause an increase in costs. This is shown by the literature on the Californian Proposition 37 where an economic study estimates that the yearly household food costs would increase by some $350 .

The issue with genetically altered corn and soy is that roundup is spliced in to the plant gene so that insects eating the plant die – cause of death? Exploding the insects’ stomach and intestines. Now, I think you should look more at the huge increase in stomach and pancreatic cancers, acid reflux disease, and other disorders and diseases of the stomach and intestines/colon since GMO corn and soy were introduced into our diets in 1996 in the U.S. – and there has been a massive increase. Nearly everything we buy at the store has either corn or soy or cottonseed in it. I’ve even found it in breads, salad dressings, and olive oil.

2crudedudes

I think the only conclusion that can be reached logically is that more research needs to be done before people are exposed to this type of genetic manipulation. The rat cancer study is a terrible example and I wonder what the motivation is, but it doesn’t change the fact that we really don’t know what the mutations we’re creating will have in the long term.

That we haven’t found any evidence of harm doesn’t mean no harm will come from it. Before we go claiming something as “safe” (something that hasn’t been proven either) we will need some concrete evidence of it.

My biggest concern about GMOs is two-fold: A) most of the backers are paid by biotech companies, a huge conflict of interest; and B) the fact that so-called scientists oppose the labeling of GMO food as such. If GMOs are really that safe, why not let the public make their own choices. In the future, when people don’t drop off from cancer, it’ll serve as evidence of their safety. However, wanting to simply slip it in without warning is troubling at best.

http://www.facebook.com/people/Joe-Walsh/100000292911318 Joe Walsh

fun fact about the DDT: it’s not the chemical it’s self that was the problem, rather it was the concentration that was wreaking havoc with the ecosystem.

Shadeburst

For the last 30 years, diabetic insulin has been manufactured from GMO yeast instead of being extracted from the pancreases of slaughtered pigs. Diabetics typically inject themselves three or four times a day. So far, no ill effects whatsoever.

noka

“I am dumping my subscription because that’s what I do when science doesn’t agree with my bias.”

noka

How said, just another person unwilling to believe the science because their bias doesn’t agree. You are the climate deniers of the left.

noka

There have been many times more when the assurances were correct. Most things do not kill you. You just disproportionately remember when things were not perfect and try to apply those when your spider sense tingles. This is not a very scientific approach to the world.

Pit Boss

Doesn’t science specifically say we should now attempt to replicate this study as many times as possible in an effort to rule it out as a real issue? Why is the first response by the “science” community to throw out the results and tell everyone to forget what they saw? Why is Discover Magazine supporting anti-science?

justa citizen

What were the rates in the female rat studies? i see the general point of the studies issues but the facts still stand. The female numbers were higher and quite alarming along with other info gathered during this study. Funny-it wasn’t mentioned here… Still a one sided opinion paper not giving any real info but trying to knock down a rising hype for peoples right to choose! VERY ONE SIDED ARTICLE. This writer should be ashamed to slant the numbers in favor of moving peoples opinions -not based on fact, but instead on personal belief!